The aim of this research is the total synthesis of the Cephalotaxus group of alkaloids, especially the harringtonines which have shown significant inhibitory action against experimental lymphoid leukemia. The harringtonines (1-4) are esters of the parent alkaloid cephalotaxine (5), which we have already synthesized. Neither cephalotaxine nor the acid moieties show activity alone. Esterification is vital for antitumor activity. In addition we hope to synthesize the structurally related oxycephalotaxines, some of lycorine group of Amaryllidaceae alkaloids, and the newly discovered "homolycorine" alkaloids cocculin and cocculidine. We hope that properly esterified members of these groups or their analogs will show antitumor properties. In addition we hope to synthesize the unusual loline group of Pyrrolizidine alkaloids in order to investigate potential antitumor activity in this series. Finally, we wish to investigate biologically active metabolites produced by the basidiomycete Phlebia strigosozonata.